fs/squashfs: sqfs_read_directory_table: fix memory leak

pos_list wasn't freed on every error

Reviewed-by: Joao Marcos Costa <jmcosta944@gmail.com>
Signed-off-by: Richard Genoud <richard.genoud@posteo.net>

diff --git a/fs/squashfs/sqfs.c b/fs/squashfs/sqfs.c
index 58b8bfc..9d460e8 100644 (file)
--- a/fs/squashfs/sqfs.c
+++ b/fs/squashfs/sqfs.c
@@ -722,6 +722,8 @@ static int sqfs_read_directory_table(unsigned char **dir_table, u32 **pos_list)
        unsigned long dest_len = 0;
        bool compressed;
 
+       *dir_table = NULL;
+       *pos_list = NULL;
        /* DIRECTORY TABLE */
        table_size = get_unaligned_le64(&sblk->fragment_table_start) -
                get_unaligned_le64(&sblk->directory_table_start);
@@ -736,35 +738,31 @@ static int sqfs_read_directory_table(unsigned char **dir_table, u32 **pos_list)
                return -ENOMEM;
 
        if (sqfs_disk_read(start, n_blks, dtb) < 0)
-               goto free_dtb;
+               goto out;
 
        /* Parse directory table (metadata block) header */
        ret = sqfs_read_metablock(dtb, table_offset, &compressed, &src_len);
        if (ret)
-               goto free_dtb;
+               goto out;
 
        /* Calculate total size to store the whole decompressed table */
        metablks_count = sqfs_count_metablks(dtb, table_offset, table_size);
        if (metablks_count < 1)
-               goto free_dtb;
+               goto out;
 
        *dir_table = malloc(metablks_count * SQFS_METADATA_BLOCK_SIZE);
        if (!*dir_table)
-               goto free_dtb;
+               goto out;
 
        *pos_list = malloc(metablks_count * sizeof(u32));
-       if (!*pos_list) {
-               free(*dir_table);
-               goto free_dtb;
-       }
+       if (!*pos_list)
+               goto out;
 
        ret = sqfs_get_metablk_pos(*pos_list, dtb, table_offset,
                                   metablks_count);
        if (ret) {
                metablks_count = -1;
-               free(*dir_table);
-               free(*pos_list);
-               goto free_dtb;
+               goto out;
        }
 
        src_table = dtb + table_offset + SQFS_HEADER_SIZE;
@@ -780,8 +778,7 @@ static int sqfs_read_directory_table(unsigned char **dir_table, u32 **pos_list)
                                              &dest_len, src_table, src_len);
                        if (ret) {
                                metablks_count = -1;
-                               free(*dir_table);
-                               goto free_dtb;
+                               goto out;
                        }
 
                        if (dest_len < SQFS_METADATA_BLOCK_SIZE) {
@@ -803,7 +800,13 @@ static int sqfs_read_directory_table(unsigned char **dir_table, u32 **pos_list)
                src_table += src_len + SQFS_HEADER_SIZE;
        }
 
-free_dtb:
+out:
+       if (metablks_count < 1) {
+               free(*dir_table);
+               free(*pos_list);
+               *dir_table = NULL;
+               *pos_list = NULL;
+       }
        free(dtb);
 
        return metablks_count;